Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

+ Details

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

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Balance Type:	credit
Period Type:	instant

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

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Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	na
Period Type:	duration

- Definition

Period remaining until the derivative contract matures, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

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- Details

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- Details

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Long-Term Debt and Short-Term Borrowings - Long-Term Debt Issuances (Details) € in Millions, $ in Millions	1 Months Ended
	Oct. 31, 2017 USD ($)	Aug. 31, 2015 USD ($)	Dec. 31, 2017 USD ($)	Sep. 30, 2016 USD ($)	May 31, 2016 EUR (€)	May 31, 2015 EUR (€)
Fixed rate medium term note due 2020
Debt instrument
Principal amount			$ 200.0
Interest rate - effective			1.49%
Fixed rate medium term notes due 2023
Debt instrument
Principal amount	$ 650.0		$ 650.0
Term of debt instrument	5 years 6 months
Interest rate - effective	2.25%		2.26%
Fixed rate medium term notes due 2027
Debt instrument
Principal amount	$ 850.0		$ 850.0
Term of debt instrument	10 years
Interest rate - effective	2.875%		2.95%
Fixed rate medium term notes due 2047
Debt instrument
Principal amount	$ 500.0		$ 500.0
Term of debt instrument	30 years
Interest rate - effective	3.625%		3.68%
May 2016 Euro medium term notes issued
Debt instrument
Principal amount \| €					€ 1,000.0
September 2016 medium term notes issued
Debt instrument
Principal amount				$ 1,750.0
May 2015 Euro medium term notes issued
Debt instrument
Principal amount \| €						€ 1,750.0
August 2015 medium term notes issued
Debt instrument
Principal amount		$ 1,500.0
Interest rate swap contracts \| Fixed rate medium term note due 2020
Debt instrument
Derivative notional amount		$ 300.0
Term of derivative contract		5 years
Interest rate swap contracts \| Fixed rate medium term note due 2018
Debt instrument
Derivative notional amount		$ 450.0
Term of derivative contract		3 years